Heat dissipating fan

ABSTRACT

A heat dissipating fan has a round disk. The bottom of the round disk has a receiving portion concave upwards for receiving a motor  14.  A periphery of the round disk has a plurality of cambered extending blades which are arranged regularly. The plurality of blades extends along a cambered path. Each blade has a convex surface and a concave surface. Each convex surface has a protruding flow guide opposite to the concave surface of the blade; and at a connection of the flow guide and the blade has at least one cambered surface.

FIELD OF THE INVENTION

[0001] The present invention relates to a heat dissipating fan, andespecially to a heat dissipating fan having cambered blades each havinga convex surface.

BACKGROUND OF THE INVENTION

[0002] In order to match the compact size of current notebook computer,air flow of heat dissipating fan is changed from the longitudinal outputto a transversal output (such as a blower). The prior art heatdissipating fan is illustrated in FIGS. 8 and 9. The periphery of therotary disk 81 is extended with blades 82 with cambered surfaces. Eachblade 82 has a tilt wind cutting angle α. Furthermore, wind is guidedalong the cambered surface of the blade and wind pressure is boosted sothat air is boosted to be pushed out. However, this kind of fan has onlythe function of absorbing air at the upper side and outputting air fromthe lateral side. Therefore, it only dissipates heat at a singledirection. It is not suitable for the device which needs to dissipateheat at the upper and lower sides. Furthermore, the blade 82 only cuts alittle air in a cutting angle α. Although the noise generated issmaller, the absorbing air is small. Next, this heat dissipating fan ismade by injecting plastics for reducing cost. However, the molds used ininjection must match with the cambered surface of the blade 82 having acomplex shape. Therefore, the mold can not be formed by an upper and alower mold. Thus, a plurality of mold cores (not shown) must be designedto be inserted into the blades 82. However, the mold has a complexstructure and a high cost. This is not suitable for the parts necessaryto reduce cost.

[0003] Another prior art design is illustrated in FIGS. 10 and 11, inthat a plurality of straight blades 92 are protruded slightly from theperiphery of the rotary disk 91 so that air is absorbed at the upper andlower sides. As a result, heat is dissipated from the upper and lowersides. In manufacturing, the complex structure of the mold in thecutting type heat dissipating fan is improved. The mold can be formed byan upper and lower molds. However, as this kind of blades 92 rotates,instead of cutting air, they beat air to induce a large amount of air.Furthermore, as the blades 92 beat air, the air at the upper and loweredges of the blades will be extruded out so as to be formed with aresisting force. This resisting force will affect the load of the motor(not shown), and thus, the lifetime of the motor is reduced.

SUMMARY OF THE INVENTION

[0004] Accordingly, the primary object of the present invention is toprovide a heat dissipating fan, wherein by the cambered surfaces of theblades, air from the upper and lower wind inlets can be driven so as tohave a preferred heat dissipating effect.

[0005] To achieve above objects, the present invention provides a heatdissipating fan, the cambered surface of the blade will cut air andincrease the flow guiding. Therefore, noise is reduced and moreover, theair will not be turbulent to the upper and lower sides. The resistanceto the absorbed air is reduced and further air is increased. Thus, theload of the motor is reduced, thereby causing the lifetime of the motorto be prolonged.

[0006] The various objects and advantages of the present invention willbe more readily understood from the following detailed description whenread in conjunction with the appended drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007]FIG. 1 is a perspective view of the first embodiment in thepresent invention.

[0008]FIG. 2 is a top view of the first embodiment in the presentinvention, wherein the arrow indicates the direction of air flow.

[0009]FIG. 3 is a lateral view of the first embodiment of the presentinvention, wherein the arrow shows the direction of air flow.

[0010]FIG. 4 is a schematic view showing the application of the firstembodiment of the present invention.

[0011]FIG. 5 is a cross sectional view along the line V-V of FIG. 4.

[0012]FIG. 6 is a lateral view of the second embodiment of the presentinvention.

[0013]FIG. 7 is a lateral view of the third embodiment of the presentinvention.

[0014]FIG. 8 is a perspective view of a prior art heat dissipating fan.

[0015]FIG. 9 is a lateral view of FIG. 8.

[0016]FIG. 10 is a perspective view of another prior art heatdissipating fan.

[0017]FIG. 11 is a lateral view of FIG. 10.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Referring to FIGS. 1 to 5, the heat dissipating fan of thepresent invention is illustrated. The heat dissipating fan of thepresent invention is installed to a casing 10. The top of the bottom ofthe casing 10 has respective wind inlets 13. The lateral side of thecasing 10 has a wind outlet 12. The inner side of the wind inlet at thebottom of the casing 10 is installed with a retaining disk 13. Thecenter of the retaining disk 13 is installed with a motor 14. The motor14 has a rotary shaft 141 extending upwards. The upper end of the rotaryshaft 141 is combined to a center of a round disk. The bottom of theround disk 20 has a receiving portion 22 concave upwards. The motor 14is received in the receiving portion 22. The periphery of the round disk20 has a plurality of cambered extending blades 21. The plurality ofblades 21 are extended counterclockwise (viewing downwards). An angle of15 to 75 degrees is formed between each blade and the normal line L atthe connection of the round disk. Each blade is installed with a convexsurface 211 and a concave surface 212. The middle portion of one side ofthe convex surface 211 has a flow guide 213 projected at an oppositeposition of the concave surface 212 of the blade 21. At the connectingportion of the flow guide 213 and the blades 21 has a cambered surface214.

[0019] It should be appreciated that as the present invention is drivenby the motor 14 so as to rotate counterclockwise (viewing downwards),the periphery of the casing 10 is formed with a turbulent space H. Eachblade 21 at the periphery of the round disk 20 will cut the wind at thefront end of the rotating path. As the air is cut, it is pushed forwardsby the convex surface 211 of the blade 21. Then, the air is driven away,while air at other portion flows into the wind inlet 11. Another, theair cut away flows to the opening end of the blade 21 along the camberedsurface 214 of the convex surface 211 (as FIGS. 2 and 3). After the airis left from the blade 21, it become as a boosting pressure in theturbulent space H of the casing 10. Then the boosted air is vented outfrom the wind outlet 12.

[0020] In one application of the present invention, it is installedwithin a notebook computer (not shown), since as the present inventionis driven by a motor 14, the flow guide 213 of the blade 12 willseparate a space into two cambered surfaces 214 so that air flows fromthe upper and lower wind inlets 11 are driven by the blade 21. The upperand lower side of the blade 21 can cut the air. Therefore, the upper andlower wind inlets 11 of the casing 10 have the function of absorbingheat. Therefore, in the present invention, air is inputted from theupper and lower sides so as to have a preferred heat dissipating effect.Furthermore, as each blade 21 cuts air, air flows to the inner sidethereof and the outer edge (as illustrated in FIG. 3) of the blade 21.The cut air do not flow to the upper and lower sides and therefore, itmakes no resistance force to the absorbed air from the wind inlet 11.When the resistance of the inlet air is decreased, the load of the motor14 is also reduced. Thus, the lifetime of the motor 14 will increase.The blade 21 of the present invention cuts air by the cambered surface214 thereof to increase the guide of air. It is not by beating, and thusnoise is reduced. Next, since the blade 21 of the present invention hasno complex curved surface, it can be made by an upper and a lower moldso that the cost is low.

[0021] In summary, the blades 21 of the heat dissipating fan accordingto the present invention may drive the air from the upper and lower windinlets 11 so as to have a preferred heat dissipating effect. Thecambered surface 214 of the blade 21 will cut air and increase the flowguiding. Therefore, noise is reduced and moreover, the air will not beturbulent to the upper and lower sides. The resistance to the absorbedair is reduced and further air is increased. Thus, the load of the motor14 is reduced, thereby causing the lifetime of the motor 14 to beprolonged. Furthermore, by the design of the flow guide 213 of the blade21, the mold can be designed easily and therefore, manufacturing cost isincreased.

[0022] Of course, many embodiments may embody the present invention. Oneof the embodiment is illustrated in FIG. 6, which is the secondembodiment of the present invention. In the present invention, the flowguide 32 of the blade 31 is installed at the bottom edge. Only an uppercambered surface 34 is formed between the flow guide 32 and the convexsurface 33. That is, the blade 31 has a preferred effect to drive airfrom the upper wind inlet (not shown) so that the present invention hasthe same function as the prior art.

[0023] Referring to FIG. 7, a third embodiment of the present inventionis illustrated. In this embodiment, a flow guide 41 is installed to benear the top edge of the blade 42 so that the each blade 42 hasdifferent cambered surface 43, thereby causing the flow guides 41 of theblade 42 to have different widths in the upper and lower sides to matchthe areas of the wind inlets (not shown).

[0024] The present invention are thus described, it will be obvious thatthe same may be varied in many ways. Such variations are not to beregarded as a departure from the spirit and scope of the presentinvention, and all such modifications as would be obvious to one skilledin the art are intended to be included within the scope of the followingclaims.

What is claimed is:
 1. A heat dissipating fan having a round disk, abottom of the round disk having a receiving portion concave upwards; aperiphery of the round disk having a plurality of cambered extendingblades; the plurality of blades extending along a cambered path; eachblade having a convex surface and a concave surface; each convex surfacehaving a protruding flow guide opposite to the concave surface of theblade; and at a connection of the flow guide and the blade having atleast one cambered surface.
 2. The heat dissipating fan as claimed inclaim 1, wherein the round disk and the plurality of blades areinstalled in a casing, an top and a bottom of the casing having a windinlet, respectively, and one lateral side of the casing has a windoutlet; an inner side of the wind inlet at the bottom of the casing hasa retaining disk; a center of the round disk being installed with amotor; the motor having a rotary shaft extending upwards; and an upperend of the rotary shaft being combined to a center of the round disk. 3.The heat dissipating fan as claimed in claim 2, wherein the receivingportion of the round disk receives the motor.
 4. The heat dissipatingfan as claimed in claim 1, wherein an angle of 15 to 75 degrees isformed between each blade and a normal line L of a connection of theround disk.
 5. The heat dissipating fan as claimed in claim 1, whereinthe flow guide is installed at the upper and lower sides of the blade.6. The heat dissipating fan as claimed in claim 1, wherein the flowguide is installed at a lower edge of the blade.
 7. The heat dissipatingfan as claimed in claim 1, wherein the flow guide is installed at theblade near a lower edge or a top edge.